04 - Menq 2003
04 - Menq 2003
04 - Menq 2003
ABSTRACT: Compacted gravel is often used as engineered fill to provide the needed bearing capacity for structures. The dynamic
properties of the gravel fill, such as nonlinear shear modulus, are required in seismic analyses to evaluate the response to dynamic
loading. From a series of Resonant Column and Torsional Shear (RCTS) tests on two types of crushed gravel fill, normalized shear
modulus reduction curves were obtained as a function of cyclic shear strain. These curves are presented and compared to empirical
relationships in the literature that have been proposed for gravelly soils.
RÉSUMÉ: Le gravier compacté est souvent utilisé comme remplissage pour fournir la capacité portante nécessaire aux structures. Les
propriétés dynamiques du remblai de gravier, tels que le module non linéaire de cisaillement, sont requises dans les analyses
sismiques pour évaluer la réponse à un chargement dynamique. A partir d'une série d’essais à la colonne de résonance et d’essais de
cisaillement en torsion sur deux types de gravier concassé de remplissage, les courbes d’évolution du module de cisaillement
normalisé ont été obtenues en fonction de la contrainte de cisaillement cyclique. Ces courbes sont présentées et comparées à des
relations empiriques provenant de la littérature qui ont été proposées pour les sols graveleux.
KEYWORDS: Shear Modulus, Resonant Column Test, Torsional Shear Test, Fill, Gravel.
(CTX), cyclic simple shear (CSS), cyclic torsional shear (TS), (Rollins et al., 1998)
and resonant-column (RC) tests. These tests not only give the
0.4
values of G and D at small strain, but also yield the variation of
G and D with and 0. However, such tests are rarely Variation Range for
performed on gravels, due to the large size of the testing 0.2
Gravel (Seed et al., 1986)
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Proceedings of the 18th International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
were carried out at loading frequency in the range from about Gravel Sand Fines
100
0.01 Hz to 0.2 Hz.
Menq (2003) used both an RCTS device and an MMD 90
WA-2, and WA-3) and one batch of the PA material (PA-1) Note: D50 is the particle diameter corresponding to 50% passing; Cc is
the coefficient of curvature, Gs is the specific gravity, and wopt is the
were taken for testing.
optimum moisture content.
Modified Proctor tests in accordance with ASTM D1557
were performed on the WA material (WA-1 and WA-3) after Table 2. Mechanical properties of gravel specimens tested in the RCTS
removing/scalping particles greater than 19 mm in diameter. device.
The modified Proctor test is not applicable to the PA material Water Dry
according to ASTM 1157. To be consistent with the modified Sample
Name
Specimen Content
Saturation
(%)
Density
Void
Ratio
Proctor test, all the other laboratory tests were also performed (%) (Mg/m3)
on the scalped material. Figure 2 shows the typical grain size PA-1
A 1 3.5 1.57 0.81
distribution curves for the tested materials (i.e., PA and WA), as B 0.8 3.2 1.66 0.70
A 6.4 72.1 2.19 0.24
well as the grain size distribution curves of each batch of the WA-1
B 6.1 85.5 2.27 0.19
material after scalping particles greater than 19 mm in diameter A 5.5 59.8 2.17 0.25
WA-2
(i.e., PA-1, WA-1, WA-2, and WA-3). B 4.4 65.3 2.30 0.18
In addition, maximum and minimum index densities were WA-3
A 5.8 61.5 2.23 0.27
B 6.2 87.2 2.35 0.20
obtained based on ASTM 4254 and ASTM 4253 for both the
PA material (PA-1) and the WA material (WA-1 and WA-3).
As seen in Table 1, the maximum index density of the WA
4 RCTS TESTS ON COMPACTED GRAVEL
material determined using a vibratory table is very close to the
maximum density obtained by impact compaction in which the During RCTS testing, the specimen is sealed in a membrane,
moisture-density relationship is defined. But comparison shows and the pore pressure in the specimen is vented to atmosphere
that the maximum index density of the WA material is pressure. From the results of cyclic triaxial tests on Toyoura
significantly (about 40%) higher than that of the PA material, sand, Kokusho (1980) indicated that the drained tests and the
which is understandable as the voids between the larger undrained tests give almost identical strain-dependent variation
of the modulus within the strain level from 10-4% to 0.5%.
Since the gravel specimens have larger permeability due to the
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Technical Committee 203 / Comité technique 203
larger grain sizes and the maximum shear strain reached in the 1.0
PA-1-A
RCTS tests were less than 0.5%, the effect of the drainage PA
The slope of the line connecting the end points of the hysteresis Shearing Strain, (% )
loop is the secant shear modulus, G, representing the average (a) Isotropic Confining Pressure = 52 kPa
shear stiffness of the soil at the peak strain in the test. Only TS 1.0
test results at a loading frequency of 0.5 Hz and measured for PA PA-1-A
the 10th cycle are presented here, as it best represents typical 0.9
0.9
Normalized Shear Modulus, G/Gmax
0.8
5 NORMALIZED SHEAR MODULUS OF COMPACTED
GRAVEL 0.7
WA-1-A
0.6 WA
In Figures 3, the measured G/Gmax ~ log( curves for the RC
WA-2-A
0.5
specimens under the different confining pressures are presented. WA-3-A
The circular and triangular symbols represent the measured data 0.4 WA-3-B
points from RC and TS tests, respectively, and the thin lines and 0.3
thick lines connect data points of the WA specimens and PA 0.2
specimens, respectively. The value of G/Gmax decreases with the Confining Pressure = 414 kPa
increasing above a threshold strain (t) for all gravel 0.1
when shear strain surpassed 0.1%, the measured shear moduli of Shearing Strain, (% )
specimens with 60% and 80% of gravel content increase with (c) Isotropic Confining Pressure = 414 kPa
increasing shear strain, and indicated this different behavior 1.0
might be attributed to the effect of gap-graded grain size
0.9
distribution. The values of t range from about 0.00015% to
Normalized Shear Modulus, G/G max
WA-1-A
0.0005% for the WA specimens, and are slightly larger for the 0.8 WA-1-B
PA material, showing an increase as 0’ increases, similar to 0.7 RC
WA-2-A
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Proceedings of the 18th International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
0.5
WA (414 kPa) based on sub-rounded river gravel suggested by Menq (2003) to
WA (827 kPa)
describe the G/Gmax ~ log( relationship correctly indicates the
0.4
effect of Cu on the G/Gmax ~ log( curves, but comparison with
0.3 this study shows the effect of Cu is somewhat different for
Variation Range
0.2 (Seed et al., 1986)
crushed gravel.
0.1
Average (Seed et al., 1986)
0.0 7 REFERENCES
0.0001 0.001 0.01 0.1 1
Cyclic Shear Strain, (% ) Darendeli B.M. 2001. Development of a new family of normalized
(a) Compared to Seed et al. (1986) and Rollins et al. (1998) modulus reduction and material damping curves. Ph. D.
Dissertation, Univ. of Texas at Austin., TX, USA, 362.
1.0
PA (52 kPa) Goto S., Nishio S. and Yoshimi Y. 1994. Dynamic properties of gravels
0.9
PA (207 kPa)
sampled by ground freezing. Ground failures under seismic
0.8
conditions. GSP No. 44, ASCE, 141–157.
52, 207 kPa; Cu = 2.1 Goto S., Suzuki Y., Nishio S. and Oh-oka H. 1992. Mechanical
0.7 WA (52 kPa) (Menq, 2003) properties of undisturbed tone-river gravel obtained by in-situ
0.6 WA (207 kPa) freezing method. Soils and Foundations, 32 (3): 15–25.
Hatanaka M. and Uchida A. 1994. Effects of test methods on the cyclic
G/Gmax
WA (414 kPa)
0.5
WA (827 kPa) deformation characteristics of high quality undisturbed gravel
0.4 samples. Static and dynamic properties of gravel soils, GSP No. 56,
ASCE, 136–151.
0.3
Hwang S.K. 1997. Investigation of the dynamic properties of natural
0.2 soils, Ph.D. Dissertation, University of Texas at Austin, 394.
Ishihara K. 1996. Soil behavior in earthquake geotechnics, Oxford
0.1 52, 207, 414, 827 kPa; Cu = 150 (Menq, 2003)
Science Publications, 350.
0.0 Kokusho T. 1980. Cyclic triaxial test of dynamic soil properties for
0.0001 0.001 0.01 0.1 1 wide strain range. Soils and Foundations, 20: 45-60.
Cyclic Shear Strain, (% ) Kokusho T. and Tanaka Y. 1994. Dynamic properties of gravel layers
(b) Compared to Menq (2003) investigated by in-situ freezing sampling. Ground failures under
Figure 4. G/Gmax ~ log( curves for compacted gravel in this study seismic conditions. GSP No. 44, ASCE, 121–140.
compared with gravel curves in the literature. Lin S.Y., Lin P.S., Luo H.S., Juag C.H. 2000. Shear modulus and
damping ratio characteristics of gravely deposits. Canadian
As shown in Table 1, the Cu values for WA-1 and WA-3 are Geotechnical J. 37:638–651.
174.5 and 150.6, respectively, while it is 2.1 for PA. Taking Cu Menq F.Y. 2003. Dynamic properties of sandy and gravelly soils, Ph.D.
= 150 and Cu = 2.1 separately, the relationship between G/Gmax Dissertation, University of Texas at Austin, TX, USA, 364.
and under different confining pressures can be predicted using Menq F.Y. and Stokoe K.H. 2003. Linear dynamic properties of sandy
the hyperbolic model proposed by Menq (2003) (i.e, Eq. (1)). and gravelly soils from large-scale resonant tests. Deformation
Characteristics of Geomaterials, Swets & Zeitlinger, Lisse, 63-71.
Menq (2003)’s predictions are compared with the results from Ni S.H. 1987. Dynamic Properties of Sand Under True Triaxial Stress
this study in Figure 4(b). The measured G/Gmax ~ log( curves States from Resonant Column/Torsional Shear Tests. Ph.D.
of the WA material degrade somewhat less than those predicted Dissertation, University of Texas at Austin, TX, USA, 421.
using Menq (2003), while the G/Gmax ~ log( curves of the PA Rollins K.M., Evans M., Diehl N. and Daily W. 1998. Shear modulus
material degrade somewhat more than the predicted curves. The and damping relationships for gravels. J. of Geotechnical and
comparison shows that effect of Cu determined using sub- Geoevironmental Engrg., 124 (5), 396-405.
rounded river gravel (Menq, 2003) is less significant for crushed Seed H.B., Wong R.T., Idriss I.M., and Tokimatsu K. 1986. Moduli and
gravels used in this study. Also, it should be noted that model damping factors for dynamic analyses of cohesionless soils. J. of
recommended by Menq (2003) is based on dry specimens with Geotechnical Engineering, 112 (11), 1016-1032.
Zhang J., Andrus R.D., and Juang C.H. 2005. Normalized Shear
few to no fines, maximum particle size of 25 mm, 19.1 mm ≥ Modulus and Material Damping Relationships. J. of Geotechnical
D50 ≥ 0.11 mm, 50 ≥ Cu ≥ 1.1, 405 kPa ≥ 0' ≥ 14.2 kPa, and 1.1 and Geoenvironmental Engineering, 131(4): 453-464.
≥ e ≥ 0.23, and some of the tested gravel specimens are outside
of this range.
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